| 1 | package be.nikiroo.utils.serial; |
| 2 | |
| 3 | import java.awt.image.BufferedImage; |
| 4 | import java.io.IOException; |
| 5 | import java.io.NotSerializableException; |
| 6 | import java.lang.reflect.Array; |
| 7 | import java.lang.reflect.Constructor; |
| 8 | import java.lang.reflect.Field; |
| 9 | import java.lang.reflect.Modifier; |
| 10 | import java.util.HashMap; |
| 11 | import java.util.Map; |
| 12 | import java.util.UnknownFormatConversionException; |
| 13 | |
| 14 | import be.nikiroo.utils.ImageUtils; |
| 15 | |
| 16 | /** |
| 17 | * Small class to help with serialisation. |
| 18 | * <p> |
| 19 | * Note that we do not support inner classes (but we do support nested classes) |
| 20 | * and all objects require an empty constructor to be deserialised. |
| 21 | * <p> |
| 22 | * It is possible to add support to custom types (both the encoder and the |
| 23 | * decoder will require the custom classes) -- see {@link CustomSerializer}. |
| 24 | * <p> |
| 25 | * Default supported types are: |
| 26 | * <ul> |
| 27 | * <li>NULL (as a null value)</li> |
| 28 | * <li>String</li> |
| 29 | * <li>Boolean</li> |
| 30 | * <li>Byte</li> |
| 31 | * <li>Character</li> |
| 32 | * <li>Short</li> |
| 33 | * <li>Long</li> |
| 34 | * <li>Float</li> |
| 35 | * <li>Double</li> |
| 36 | * <li>Integer</li> |
| 37 | * <li>Enum (any enum whose name and value is known by the caller)</li> |
| 38 | * <li>java.awt.image.BufferedImage (as a {@link CustomSerializer})</li> |
| 39 | * <li>An array of the above (as a {@link CustomSerializer})</li> |
| 40 | * </ul> |
| 41 | * |
| 42 | * @author niki |
| 43 | */ |
| 44 | public class SerialUtils { |
| 45 | private static Map<String, CustomSerializer> customTypes; |
| 46 | |
| 47 | static { |
| 48 | customTypes = new HashMap<String, CustomSerializer>(); |
| 49 | |
| 50 | // Array types: |
| 51 | customTypes.put("[]", new CustomSerializer() { |
| 52 | @Override |
| 53 | protected String toString(Object value) { |
| 54 | String type = value.getClass().getCanonicalName(); |
| 55 | type = type.substring(0, type.length() - 2); // remove the [] |
| 56 | |
| 57 | StringBuilder builder = new StringBuilder(); |
| 58 | builder.append(type).append("\n"); |
| 59 | try { |
| 60 | for (int i = 0; true; i++) { |
| 61 | Object item = Array.get(value, i); |
| 62 | // encode it normally if direct value |
| 63 | if (!SerialUtils.encode(builder, item)) { |
| 64 | try { |
| 65 | // use ZIP: if not |
| 66 | builder.append(new Exporter().append(item) |
| 67 | .toString(true)); |
| 68 | } catch (NotSerializableException e) { |
| 69 | throw new UnknownFormatConversionException(e |
| 70 | .getMessage()); |
| 71 | } |
| 72 | } |
| 73 | builder.append("\n"); |
| 74 | } |
| 75 | } catch (ArrayIndexOutOfBoundsException e) { |
| 76 | // Done. |
| 77 | } |
| 78 | |
| 79 | return builder.toString(); |
| 80 | } |
| 81 | |
| 82 | @Override |
| 83 | protected String getType() { |
| 84 | return "[]"; |
| 85 | } |
| 86 | |
| 87 | @Override |
| 88 | protected Object fromString(String content) { |
| 89 | String[] tab = content.split("\n"); |
| 90 | |
| 91 | try { |
| 92 | Object array = Array.newInstance( |
| 93 | SerialUtils.getClass(tab[0]), tab.length - 1); |
| 94 | for (int i = 1; i < tab.length; i++) { |
| 95 | Object value = new Importer().read(tab[i]).getValue(); |
| 96 | Array.set(array, i - 1, value); |
| 97 | } |
| 98 | |
| 99 | return array; |
| 100 | } catch (Exception e) { |
| 101 | throw new UnknownFormatConversionException(e.getMessage()); |
| 102 | } |
| 103 | } |
| 104 | }); |
| 105 | |
| 106 | // Images (this is currently the only supported image type by default) |
| 107 | customTypes.put("java.awt.image.BufferedImage", new CustomSerializer() { |
| 108 | @Override |
| 109 | protected String toString(Object value) { |
| 110 | try { |
| 111 | return ImageUtils.toBase64((BufferedImage) value); |
| 112 | } catch (IOException e) { |
| 113 | throw new UnknownFormatConversionException(e.getMessage()); |
| 114 | } |
| 115 | } |
| 116 | |
| 117 | @Override |
| 118 | protected String getType() { |
| 119 | return "java.awt.image.BufferedImage"; |
| 120 | } |
| 121 | |
| 122 | @Override |
| 123 | protected Object fromString(String content) { |
| 124 | try { |
| 125 | return ImageUtils.fromBase64(content); |
| 126 | } catch (IOException e) { |
| 127 | throw new UnknownFormatConversionException(e.getMessage()); |
| 128 | } |
| 129 | } |
| 130 | }); |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Create an empty object of the given type. |
| 135 | * |
| 136 | * @param type |
| 137 | * the object type (its class name) |
| 138 | * |
| 139 | * @return the new object |
| 140 | * |
| 141 | * @throws ClassNotFoundException |
| 142 | * if the class cannot be found |
| 143 | * @throws NoSuchMethodException |
| 144 | * if the given class is not compatible with this code |
| 145 | */ |
| 146 | public static Object createObject(String type) |
| 147 | throws ClassNotFoundException, NoSuchMethodException { |
| 148 | |
| 149 | try { |
| 150 | Class<?> clazz = getClass(type); |
| 151 | String className = clazz.getName(); |
| 152 | Object[] args = null; |
| 153 | Constructor<?> ctor = null; |
| 154 | if (className.contains("$")) { |
| 155 | Object javaParent = createObject(className.substring(0, |
| 156 | className.lastIndexOf('$'))); |
| 157 | args = new Object[] { javaParent }; |
| 158 | ctor = clazz.getDeclaredConstructor(new Class[] { javaParent |
| 159 | .getClass() }); |
| 160 | } else { |
| 161 | args = new Object[] {}; |
| 162 | ctor = clazz.getDeclaredConstructor(); |
| 163 | } |
| 164 | |
| 165 | ctor.setAccessible(true); |
| 166 | return ctor.newInstance(args); |
| 167 | } catch (ClassNotFoundException e) { |
| 168 | throw e; |
| 169 | } catch (NoSuchMethodException e) { |
| 170 | throw e; |
| 171 | } catch (Exception e) { |
| 172 | throw new NoSuchMethodException("Cannot instantiate: " + type); |
| 173 | } |
| 174 | } |
| 175 | |
| 176 | /** |
| 177 | * Insert a custom serialiser that will take precedence over the default one |
| 178 | * or the target class. |
| 179 | * |
| 180 | * @param serializer |
| 181 | * the custom serialiser |
| 182 | */ |
| 183 | static public void addCustomSerializer(CustomSerializer serializer) { |
| 184 | customTypes.put(serializer.getType(), serializer); |
| 185 | } |
| 186 | |
| 187 | /** |
| 188 | * Serialise the given object into this {@link StringBuilder}. |
| 189 | * <p> |
| 190 | * <b>Important: </b>If the operation fails (with a |
| 191 | * {@link NotSerializableException}), the {@link StringBuilder} will be |
| 192 | * corrupted (will contain bad, most probably not importable data). |
| 193 | * |
| 194 | * @param builder |
| 195 | * the output {@link StringBuilder} to serialise to |
| 196 | * @param o |
| 197 | * the object to serialise |
| 198 | * @param map |
| 199 | * the map of already serialised objects (if the given object or |
| 200 | * one of its descendant is already present in it, only an ID |
| 201 | * will be serialised) |
| 202 | * |
| 203 | * @throws NotSerializableException |
| 204 | * if the object cannot be serialised (in this case, the |
| 205 | * {@link StringBuilder} can contain bad, most probably not |
| 206 | * importable data) |
| 207 | */ |
| 208 | static void append(StringBuilder builder, Object o, Map<Integer, Object> map) |
| 209 | throws NotSerializableException { |
| 210 | |
| 211 | Field[] fields = new Field[] {}; |
| 212 | String type = ""; |
| 213 | String id = "NULL"; |
| 214 | |
| 215 | if (o != null) { |
| 216 | int hash = System.identityHashCode(o); |
| 217 | fields = o.getClass().getDeclaredFields(); |
| 218 | type = o.getClass().getCanonicalName(); |
| 219 | if (type == null) { |
| 220 | throw new NotSerializableException( |
| 221 | String.format( |
| 222 | "Cannot find the class for this object: %s (it could be an inner class, which is not supported)", |
| 223 | o)); |
| 224 | } |
| 225 | id = Integer.toString(hash); |
| 226 | if (map.containsKey(hash)) { |
| 227 | fields = new Field[] {}; |
| 228 | } else { |
| 229 | map.put(hash, o); |
| 230 | } |
| 231 | } |
| 232 | |
| 233 | builder.append("{\nREF ").append(type).append("@").append(id) |
| 234 | .append(":"); |
| 235 | if (!encode(builder, o)) { // check if direct value |
| 236 | try { |
| 237 | for (Field field : fields) { |
| 238 | field.setAccessible(true); |
| 239 | |
| 240 | if (field.getName().startsWith("this$") |
| 241 | || field.isSynthetic() |
| 242 | || (field.getModifiers() & Modifier.STATIC) == Modifier.STATIC) { |
| 243 | // Do not keep this links of nested classes |
| 244 | // Do not keep synthetic fields |
| 245 | // Do not keep final fields |
| 246 | continue; |
| 247 | } |
| 248 | |
| 249 | builder.append("\n"); |
| 250 | builder.append(field.getName()); |
| 251 | builder.append(":"); |
| 252 | Object value; |
| 253 | |
| 254 | value = field.get(o); |
| 255 | |
| 256 | if (!encode(builder, value)) { |
| 257 | builder.append("\n"); |
| 258 | append(builder, value, map); |
| 259 | } |
| 260 | } |
| 261 | } catch (IllegalArgumentException e) { |
| 262 | e.printStackTrace(); // should not happen (see |
| 263 | // setAccessible) |
| 264 | } catch (IllegalAccessException e) { |
| 265 | e.printStackTrace(); // should not happen (see |
| 266 | // setAccessible) |
| 267 | } |
| 268 | } |
| 269 | builder.append("\n}"); |
| 270 | } |
| 271 | |
| 272 | /** |
| 273 | * Encode the object into the given builder if possible (if supported). |
| 274 | * |
| 275 | * @param builder |
| 276 | * the builder to append to |
| 277 | * @param value |
| 278 | * the object to encode (can be NULL, which will be encoded) |
| 279 | * |
| 280 | * @return TRUE if success, FALSE if not (the content of the builder won't |
| 281 | * be changed in case of failure) |
| 282 | */ |
| 283 | static boolean encode(StringBuilder builder, Object value) { |
| 284 | if (value == null) { |
| 285 | builder.append("NULL"); |
| 286 | } else if (value.getClass().getCanonicalName().endsWith("[]")) { |
| 287 | return customTypes.get("[]").encode(builder, value); |
| 288 | } else if (customTypes.containsKey(value.getClass().getCanonicalName())) { |
| 289 | return customTypes.get(value.getClass().getCanonicalName())// |
| 290 | .encode(builder, value); |
| 291 | } else if (value instanceof String) { |
| 292 | encodeString(builder, (String) value); |
| 293 | } else if (value instanceof Boolean) { |
| 294 | builder.append(value); |
| 295 | } else if (value instanceof Byte) { |
| 296 | builder.append(value).append('b'); |
| 297 | } else if (value instanceof Character) { |
| 298 | encodeString(builder, "" + value); |
| 299 | builder.append('c'); |
| 300 | } else if (value instanceof Short) { |
| 301 | builder.append(value).append('s'); |
| 302 | } else if (value instanceof Integer) { |
| 303 | builder.append(value); |
| 304 | } else if (value instanceof Long) { |
| 305 | builder.append(value).append('L'); |
| 306 | } else if (value instanceof Float) { |
| 307 | builder.append(value).append('F'); |
| 308 | } else if (value instanceof Double) { |
| 309 | builder.append(value).append('d'); |
| 310 | } else if (value instanceof Enum) { |
| 311 | String type = value.getClass().getCanonicalName(); |
| 312 | builder.append(type).append(".").append(((Enum<?>) value).name()) |
| 313 | .append(";"); |
| 314 | } else { |
| 315 | return false; |
| 316 | } |
| 317 | |
| 318 | return true; |
| 319 | } |
| 320 | |
| 321 | /** |
| 322 | * Decode the data into an equivalent source object. |
| 323 | * |
| 324 | * @param encodedValue |
| 325 | * the encoded data, cannot be NULL |
| 326 | * |
| 327 | * @return the object (can be NULL for NULL encoded values) |
| 328 | * |
| 329 | * @throws UnknownFormatConversionException |
| 330 | * if the content cannot be converted |
| 331 | */ |
| 332 | static Object decode(String encodedValue) { |
| 333 | String cut = ""; |
| 334 | if (encodedValue.length() > 1) { |
| 335 | cut = encodedValue.substring(0, encodedValue.length() - 1); |
| 336 | } |
| 337 | |
| 338 | try { |
| 339 | if (CustomSerializer.isCustom(encodedValue)) { |
| 340 | // custom:TYPE_NAME:"content is String-encoded" |
| 341 | String type = CustomSerializer.typeOf(encodedValue); |
| 342 | if (customTypes.containsKey(type)) { |
| 343 | return customTypes.get(type).decode(encodedValue); |
| 344 | } |
| 345 | throw new UnknownFormatConversionException( |
| 346 | "Unknown custom type: " + type); |
| 347 | } else if (encodedValue.equals("NULL") |
| 348 | || encodedValue.equals("null")) { |
| 349 | return null; |
| 350 | } else if (encodedValue.endsWith("\"")) { |
| 351 | return decodeString(encodedValue); |
| 352 | } else if (encodedValue.equals("true")) { |
| 353 | return true; |
| 354 | } else if (encodedValue.equals("false")) { |
| 355 | return false; |
| 356 | } else if (encodedValue.endsWith("b")) { |
| 357 | return Byte.parseByte(cut); |
| 358 | } else if (encodedValue.endsWith("c")) { |
| 359 | return decodeString(cut).charAt(0); |
| 360 | } else if (encodedValue.endsWith("s")) { |
| 361 | return Short.parseShort(cut); |
| 362 | } else if (encodedValue.endsWith("L")) { |
| 363 | return Long.parseLong(cut); |
| 364 | } else if (encodedValue.endsWith("F")) { |
| 365 | return Float.parseFloat(cut); |
| 366 | } else if (encodedValue.endsWith("d")) { |
| 367 | return Double.parseDouble(cut); |
| 368 | } else if (encodedValue.endsWith(";")) { |
| 369 | return decodeEnum(encodedValue); |
| 370 | } else { |
| 371 | return Integer.parseInt(encodedValue); |
| 372 | } |
| 373 | } catch (Exception e) { |
| 374 | if (e instanceof UnknownFormatConversionException) { |
| 375 | throw (UnknownFormatConversionException) e; |
| 376 | } |
| 377 | throw new UnknownFormatConversionException(e.getMessage()); |
| 378 | } |
| 379 | } |
| 380 | |
| 381 | /** |
| 382 | * Return the corresponding class or throw an {@link Exception} if it |
| 383 | * cannot. |
| 384 | * |
| 385 | * @param type |
| 386 | * the class name to look for |
| 387 | * |
| 388 | * @return the class (will never be NULL) |
| 389 | * |
| 390 | * @throws ClassNotFoundException |
| 391 | * if the class cannot be found |
| 392 | * @throws NoSuchMethodException |
| 393 | * if the class cannot be created (usually because it or its |
| 394 | * enclosing class doesn't have an empty constructor) |
| 395 | */ |
| 396 | static private Class<?> getClass(String type) |
| 397 | throws ClassNotFoundException, NoSuchMethodException { |
| 398 | Class<?> clazz = null; |
| 399 | try { |
| 400 | clazz = Class.forName(type); |
| 401 | } catch (ClassNotFoundException e) { |
| 402 | int pos = type.length(); |
| 403 | pos = type.lastIndexOf(".", pos); |
| 404 | if (pos >= 0) { |
| 405 | String parentType = type.substring(0, pos); |
| 406 | String nestedType = type.substring(pos + 1); |
| 407 | Class<?> javaParent = null; |
| 408 | try { |
| 409 | javaParent = getClass(parentType); |
| 410 | parentType = javaParent.getName(); |
| 411 | clazz = Class.forName(parentType + "$" + nestedType); |
| 412 | } catch (Exception ee) { |
| 413 | } |
| 414 | |
| 415 | if (javaParent == null) { |
| 416 | throw new NoSuchMethodException( |
| 417 | "Class not found: " |
| 418 | + type |
| 419 | + " (the enclosing class cannot be created: maybe it doesn't have an empty constructor?)"); |
| 420 | } |
| 421 | } |
| 422 | } |
| 423 | |
| 424 | if (clazz == null) { |
| 425 | throw new ClassNotFoundException("Class not found: " + type); |
| 426 | } |
| 427 | |
| 428 | return clazz; |
| 429 | } |
| 430 | |
| 431 | @SuppressWarnings({ "unchecked", "rawtypes" }) |
| 432 | private static Enum<?> decodeEnum(String escaped) { |
| 433 | // escaped: be.xxx.EnumType.VALUE; |
| 434 | int pos = escaped.lastIndexOf("."); |
| 435 | String type = escaped.substring(0, pos); |
| 436 | String name = escaped.substring(pos + 1, escaped.length() - 1); |
| 437 | |
| 438 | try { |
| 439 | return Enum.valueOf((Class<Enum>) getClass(type), name); |
| 440 | } catch (Exception e) { |
| 441 | throw new UnknownFormatConversionException("Unknown enum: <" + type |
| 442 | + "> " + name); |
| 443 | } |
| 444 | } |
| 445 | |
| 446 | // aa bb -> "aa\tbb" |
| 447 | private static void encodeString(StringBuilder builder, String raw) { |
| 448 | builder.append('\"'); |
| 449 | for (char car : raw.toCharArray()) { |
| 450 | switch (car) { |
| 451 | case '\\': |
| 452 | builder.append("\\\\"); |
| 453 | break; |
| 454 | case '\r': |
| 455 | builder.append("\\r"); |
| 456 | break; |
| 457 | case '\n': |
| 458 | builder.append("\\n"); |
| 459 | break; |
| 460 | case '"': |
| 461 | builder.append("\\\""); |
| 462 | break; |
| 463 | default: |
| 464 | builder.append(car); |
| 465 | break; |
| 466 | } |
| 467 | } |
| 468 | builder.append('\"'); |
| 469 | } |
| 470 | |
| 471 | // "aa\tbb" -> aa bb |
| 472 | private static String decodeString(String escaped) { |
| 473 | StringBuilder builder = new StringBuilder(); |
| 474 | |
| 475 | boolean escaping = false; |
| 476 | for (char car : escaped.toCharArray()) { |
| 477 | if (!escaping) { |
| 478 | if (car == '\\') { |
| 479 | escaping = true; |
| 480 | } else { |
| 481 | builder.append(car); |
| 482 | } |
| 483 | } else { |
| 484 | switch (car) { |
| 485 | case '\\': |
| 486 | builder.append('\\'); |
| 487 | break; |
| 488 | case 'r': |
| 489 | builder.append('\r'); |
| 490 | break; |
| 491 | case 'n': |
| 492 | builder.append('\n'); |
| 493 | break; |
| 494 | case '"': |
| 495 | builder.append('"'); |
| 496 | break; |
| 497 | } |
| 498 | escaping = false; |
| 499 | } |
| 500 | } |
| 501 | |
| 502 | return builder.substring(1, builder.length() - 1).toString(); |
| 503 | } |
| 504 | } |